AP_UAVCAN: fixed build on Linux

libraries/AP_UAVCAN/AP_UAVCAN.h

@@ -176,7 +176,7 @@ private:
     uavcan::Node<0> *_node;
 
     uint8_t _driver_index;
-    char _thread_name[9];
+    char _thread_name[13];
     bool _initialized;
     ///// SRV output /////
     struct {

libraries/AP_UAVCAN/AP_UAVCAN_DNA_Server.cpp

@@ -546,7 +546,7 @@ void trampoline_handleNodeInfo(const uavcan::ServiceCallResult<uavcan::protocol:
     uavcan::copy(resp.getResponse().hardware_version.unique_id.begin(),
                  resp.getResponse().hardware_version.unique_id.end(),
                  unique_id);
-    snprintf(name, ARRAY_SIZE(name), "%s", resp.getResponse().name.c_str());
+    strncpy(name, resp.getResponse().name.c_str(), sizeof(name)-1);
     AP::uavcan_dna_server().handleNodeInfo(node_id, unique_id, name);
 }